The importance of the treatment of slipping upper femoral epiphyses may be viewed in two ways: (1) the immediate result, that is, relief from pain and disability and correction of deformity, and (2) the ultimate result, which can be estimated only after the patient has reached the age of 50 or 60 years. There seems little doubt that many cases of morbus coxae senilis are based on changes resulting from a preexisting slipped epiphysis. To select these cases accurately is often difficult, for the symptoms during adolescence may have been of such a mild nature that the patient may not have been conscious of the trouble or may have forgotten it.

In order to gain a true estimate of the value of modern methods of treatment we should be able to compare the end results in cases treated by these methods with the end results in those cases not treated.